Sorry to say I'm not experienced so I can't give a perfect answer here. Have you check proton x50 comes with both the two in the SC or website? As for the differences, 4WD transfers the power to all four wheels equally and are more suitable for poor unpaved roads with stones and rocks and extreme road condition. While AWD would vary the amount of power given to each wheel and works all the time, which suits all road conditions. My boss just said I was wrong, but you could find something valuable in it.